Interactions Of Minerals And Oil Hydrocarbons In Reservoir Rocks

This dissertation mainly investigated the interactions of minerals and oils hydrocarbons in reservoir rocks. (1) Clay minerals adsorption of oils and gases in sandstones. We mainly studied the difference of geochemical characteristics between clay-adsorbed oils and other oils. Oil filling history also has been investigated. (2) Using simulation experiments to study the oxidation of gaseous hydrocjirbons by different minerals oxidants, to show the variation of gas geochemical indexes and offer evidences to study the cause of formation of specific gas reservoirs.The sequential extraction of sandstones was firstly applied in Turpan-Hamin basin, and the analytical results indicate that the free oils, inclusion oils (oil-bearing fluid inclusions) and clay-adsorbed oils vary significantly. The geochemical characteristics of inclusion and clay-adsorbed oils correlate well with the lacustrine mudstones. They indicate that the early charged oils are derived from the pre-Jurassic lacustrine mudstones and the later charged oils are from the Jurassic coal-bearing strata or coals.Using two experiments to show the variation of proportional and carbon isotopic compositions of gaseous hydrocarbons after oxidation. First, a large number of gas hydrocarbon-bearing gold capsules were prepared by kerogen pyrolysis experiment using a same kerogen and conducted at same condition (450℃ and 50MPa for 72h). The proportional and carbon isotopic compositions of hydrocarbon and non-hydrocarbon gases are almost identical among these gold capsules. Then, a large set of experiments on gas hydrocarbon oxidation by mineral oxidant were conducted at 350 ℃ and 50MPa for different heating times. After oxidation experiments, the proportional and carbon isotopic compositions of gaseous hydrocarbons varied substantially andsystematically, in comparison with those of the initial gas components in the gas hydrocarbon-bearing capsules.